ez-efi vs holley tbi
Thread Starter
Racer
Joined: Jul 2004
Posts: 444
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From: Dallas TX
ez-efi vs holley tbi
I don't have a whole lot of hood clearance with my 80457 Holley four barrel 600cfm vacuum secondary carb perched on top a Weiand Action +Plus manifold. Having the injectors sitting above the throttle body makes the Holley tbi look pretty tall, but is any taller than the carb? I do like how the ez-efi tbi unit looks and it does claim to be short. How does that one compare to the carb?
Also, does the ez-efi work with the innovate wide band O2?
Also, does the ez-efi work with the innovate wide band O2?
The ORIGINAL and bestest
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From: Toronto Ontario
Toronto Events Coordinator
I don't have a whole lot of hood clearance with my 80457 Holley four barrel 600cfm vacuum secondary carb perched on top a Weiand Action +Plus manifold. Having the injectors sitting above the throttle body makes the Holley tbi look pretty tall, but is any taller than the carb? I do like how the ez-efi tbi unit looks and it does claim to be short. How does that one compare to the carb?
Also, does the ez-efi work with the innovate wide band O2?
Also, does the ez-efi work with the innovate wide band O2?
Safety Car
Joined: Nov 2005
Posts: 3,961
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From: Lompoc, CA. Santa Barbara County
I have the Holley TBI system and it is shorter than the Quadrajet I replaced. So much shorter, that I went from a 3" air cleaner to a 4". I could eleminate the plastic spacer and drop it down even more.
Bee Jay
Bee Jay
Racer
Joined: Sep 2003
Posts: 258
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From: Memphis TN
I have the EZ-EFI system in my 74 BB. Best mod I have ever done to the car. Throttle body is dimensionally the same as a Holley carb in every way including the throttle linkage. I am still using the same drop base air cleaner and 3" air filter I was using with my Demon.
Pro
Joined: Nov 2000
Posts: 582
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From: Madison Wisconsin
I have the Holley TBI due to Bee Jays recommendation. Its on a Weiand Team G thats 4.5" high. I had to install a 1/2" carb spacer because the top of the air cleaner would hit the injectors. But it fits under the stock hood and I can run my stock dual snorkel or I have the drop base chrome LT1 air cleaner. This is my measurement before I installed it to get me height right. 
Last edited by Mad Vette; Aug 2, 2009 at 05:49 PM.
Safety Car
Joined: Nov 2005
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From: Lompoc, CA. Santa Barbara County
Well, if the injectors are below the blades, it's pretty darn close to being a port injection system, but you have only four injectors instead of eight, and the injection is way up in the manifold plenum chamber. How much does one of these units cost? I like the way it looks. Even though I am very happy with my Holley TBI, it is first generation yestertech. But, as often quoted here, it ain't broke.
Bee Jay
Bee Jay
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The ORIGINAL and bestest
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From: Toronto Ontario
Toronto Events Coordinator
Well, if the injectors are below the blades, it's pretty darn close to being a port injection system, but you have only four injectors instead of eight, and the injection is way up in the manifold plenum chamber. How much does one of these units cost? I like the way it looks. Even though I am very happy with my Holley TBI, it is first generation yestertech. But, as often quoted here, it ain't broke.
Bee Jay
Bee Jay
Safety Car
Joined: Nov 2005
Posts: 3,961
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From: Lompoc, CA. Santa Barbara County
$2000 and it comes with wideband! Yellow fever has such excellent taste in color, he must be a good judge of fi units. I'll put this on my wish list, right under rack and pinion and an aluminum 427 small block.
Last edited by Bee Jay; Aug 2, 2009 at 10:56 AM.
The ORIGINAL and bestest
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From: Toronto Ontario
Toronto Events Coordinator
An all-aluminum 427 sb would be very cool!
Racer
Joined: Sep 2003
Posts: 258
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From: Memphis TN
Thanks for the compliment. I looked at some other FI units, like the Professional Products, but ultimately went with the FAST system because of their good reputation, the fact that my engine builder, Dwayne Watkins (former #6 ADRL Pro-Extreme record holder), was familiar with and had used one of their units on his personal blown BB 57 Chevy, and the fact that they were right here in Memphis in case I had any problems with it.
Thread Starter
Racer
Joined: Jul 2004
Posts: 444
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From: Dallas TX
Is having the injectors under the throttle plates much of an advantage? It seems like under part throttle it would be better to spray fuel directly into the manifold rather than onto the throttle plates.
Safety Car
Joined: Nov 2005
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From: Lompoc, CA. Santa Barbara County
Bee Jay
Pro
Joined: Sep 2008
Posts: 508
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From: Olive Branch MS
Hood clearance all depends on your intake with the EZefi. If a carb fits the EZefi throttlebody should, too.
Some intakes won't work under the hood, even with EZEfi...
Some intakes won't work under the hood, even with EZEfi...
Last edited by bluzman2004; Aug 4, 2009 at 01:46 PM.
Pro
Joined: Sep 2008
Posts: 508
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From: Olive Branch MS
We're just waiting on my fellow engineer to write an addition to the installation instructions. He is waiting for me to bring my car in so we can disassemble the everything and walk through it step by step. It is very close to being released. I think we even have some orders already on backorder.
